Rising provinces to strengthen Irish -- Schmidt
When Leinster surged to a 20-9 half-time lead in Thomond Park last month, Joe Schmidt's team stood on the brink of a sixth successive victory in a fixture framed by boundaries from an ancient past but renewed vigorously by professionalism.
Another defeat for the red-clad hordes would have punctured the competitive bubble within which the provincial heavyweights have operated since the start of this century.
For what is a rivalry if it is so inherently one-sided?
Mercifully for the Thomond faithful, the home side's thunderous response rescued that particular situation.
The Munster-Leinster rivalry has signposted the past few seasons of glorious achievement and the pair have undoubtedly raised each other's standards, as well as back-boning Ireland's Grand Slam success in 2009.
But Irish rugby may need more than this rivalry to sustain itself in the years to come, particularly as its leading characters begin departing the stage, which is why Ulster's revival and Connacht's ascension to the Heineken Cup could be so crucial in sustaining a remarkable legacy.
Sometimes it takes an outsider to cut through the parochial bombast and Joe Schmidt, as he has often done this season, preferred to sketch his perspective on Irish rugby upon a wider canvas.
"I wouldn't discount Ulster," he said, in reference to the side who reached the knockout stages of both competitions this season.
"To narrow it to two teams in Ireland would be a misnomer, because I am looking at the Irish U-20 squad and Ulster and Leinster almost have a split there in how many players they have got in the team.
"They have the bulk of the players so maybe Ulster are the coming team. It's a real strength when you've got a rivalry of three or four, as Connacht gain momentum in the Heineken Cup as well."
Eoin Reddan, who has seen both sides of the red-blue divide, can see some sense in his coach's view.
"I couldn't agree with it more," he said. "It's brilliant to see, especially Connacht. Players might be easier to pick up on if they play in the Heineken Cup. You might go out in the Magners League and have a stormer but it wouldn't be noticed as quick."
Nevertheless, Reddan, son of Limerick but now a three-province veteran, can't ignore the momentous occasion that awaits.
"The rivalry has been there forever," he enthused. "Whether Munster play Leinster in a friendly, a Magners League, it doesn't matter what game it is, it is always tough and I don't think this week is going to be any different.
"It will probably help both teams to focus on the match itself and not the occasion, not doubles, not the league, just simply the match."
Reddan's career path -- from Connacht to Leinster via Munster and two-time Heineken Cup champions Wasps -- is well-worn but what better week for us to press him to recall the circumstances of his departure from Munster six years ago.
It was a January morning and Reddan was heading home with a heavy heart after Alan Gaffney had told him that there would not be a new contract on the table for the local boy.
His mobile rang as he meandered homewards and Shaun Edwards' familiarly brusque tone changed his life. "It was the biggest coincidence of my life," he recalled yesterday. "I just said 'yes'. I didn't even ask about years, money or anything. It was done in five minutes. That was the way it went.
"I did speak to Wasps when I left Connacht to go to Munster but at the time I wanted to follow the dream. You grow up 15, 16 wanting to pull on the red jersey."
Now he's going home again.
"It definitely adds to it being from Limerick. All my family will be there and it will be great to be able to play in front of them.
"But the game itself will overtake that. It's a Munster team who are trying to finish their season on a high. It's going to be special."
This rivalry has some road to run yet.